Valve gear



Sept. 27, 1927.

H. GREGER` VALVE GEAR Filed NOV. 25. 1922 F1 -EZ Patented Sept. 27, 1927.

UNITED STATES A 1,643,492 TENT oFFicE.

HENRIK GREGER, OF HAMILTON, OHI, ASSIGNOR TO THE HOOVEN, OWENS, `RENT SCHLER COMPANY, 0F HAMILTON, OHIO, A CORORATON 0]?.01-110.

vALvE GEAiaf Application filed November 25, 1922. Serial No. 693,305.

This invention relates to valve gear, such as is used in connection with steam engine and the like. .V f

y One of the principalobj ects ofthe invention is to provide a new and improved formof valve gear which is simple in construction and operation, easily maintained in operating condition, andA effective and reliable in operation.

Other objects and advantages will be apparent from the description thereof set out below when taken inV connection with the accompanying drawing. l

, In the drawing,.in which like characters of reference designate like parts throughout the several views thereof; ,A K,

Fig. l is a side elevational view of asteam engine having incorporated therein the valve gear forming the subject matter of this invention; and

Fig. 2 is a plan view of the apparatus shown in Fig. l.

`While this type of valve gear is of general application, it is show-n in connectionl 'with a compound engine for driving the type of stern Wheel boat which is quite largely used on the rivers of'this country. A.

The general arrangement of the power plant of such a boat, comprises twin tandem engines, arranged on opposite sides of the boat, "these engines being connected, by means of suitable 'connecting rods vto cranks mounted upon opposite ends of the shaft ofthe paddle wheel. These cranks areV preferably positionedwith one 90O in advanceof the other.

The engines for driving the paddle wheel may be of any suitable character, but preferably they are double expansion, compound engines, each engine consistingv of al high pressure cylinder 20 and a low pressure cylinder `2l, it being understood that the two engines are exactly alike except for such slight modifications as result from the fact that they are positioned for attachment to opposite ends of the paddlel wheel shaft.

These engines are of the tandem type that is the cylinders are arranged one directly behind the other, with a single piston rod 22 functioning for both cylinders, rthis'piston rod having two pistons mounted thereon, one of which serves as the piston forthe high pressure cylinder 2O and the other as ythe piston for the low pressure cylinder 2l. The free end of the piston rod 22 is connected to a cross head 23' which, yduring reciprocation of the pistons during operation of the engine, slides back and forth along cross head' guides 24. This cross head is provided with a suitable wrist pin to which is connected one end of the respective connecting rod, the opposite end of which is connected to one of the cranks of thev paddle wheel shaft. These connecting rods may be of any desired character but in boats of the type referred to they usually consist of a wooden bar 3() which is bound around, throughout its length, with a metal strip 3l, the wooden bar and the metal strip being bolted together by means of a large number of bolts 32, this construction giving a very satisfactory type f sired. .For purposes of description ther valves in the high pressure cylinder are designated.V generally by the numeral 33 while those in the low pressure cylinder are designated by the numeral 34. yEach high pressure cylinder is provided with a transverse shaft v35,v mounted in suitable bearings, which shaft at each of its ends, is provided with. a 4wrist plate 36, rigidly attached to the shaft and adapted to oscillate therewith. Each of these wrist plates is connected 'by means of suitable rods, or the like, 37, to the. valves 33 on one side of the cylinder, oscillation of the shaft 35, with the wrist plates carried thereby, causing alternate actuation of the valves at opposite ends of the cylinder. Each shaft 35 is provided, intermediate its ends, with two upstanding arms or cranks 38, the outer ends of which have positioned therebetween one end of the rod 40, which is held in pivotal connection with the outer ends of the arms 38 by means of a suitable pin 4l. The opposite end ofthe rod l0 is similarly connected to the varms 42, of the oscillatory shaft 45, which is positioned transverse to the low pressure cylinder 2l, in suitable bearings. This shaft l5 is provided, upon opposite sides of the arms. 42, 'with wrist plates 46, which are substantially identical in construction with the wrist plates 36, and which are connected, by means ot suitable rods or the like 47, to the valves 34 of the low pressure cylinder. One end et the shaft 45 has attached thereto an arm or crank 50, which is pivotally connected to a rod 51, which rod in turn is actuated from any suitable source, to etli'ect oscillation of the sha'tt 45, to operate the valvesV of the engine. means ot this construction oscillation of the shaft 45 causes oscillation of the shalt 35 at the saine time, and thus operation of the various valves ot' the high and low pressure cylinders in proper relation, relative to each other, and in proper sequence, is insured. rlhe rod 51, at its other end, is provided with a suitable pin or block 52, which cooperates withvthe slot 53 in the sector or link 54. This link 54 is pivoted substantially midway of its length to the pivot pin 55, which is carried upon the upper` end of a second link 56, the lower end ot which is pivotally connected to the bed plate,'or some other` liked part or' the structure, as shown at 57.- The link 54 also has pivot-ally connected to its opposite ends the eccentric Yrods and 61, the eccentric rod being connected to its upper end and .the eccentric rod .61 to its lower end. Pivotally connected lto the rod 51, intermediate its ends, is a link 62, the other end of which is pivotally connected to a bell cranklever 63 which is in turn pivotally mounted upon a` suitable shait 64, the short arm of the bell crank lever being pivotally connected at 65, to vthe piston rod 66 of the reversing engine cylinder 67, which may be of any conventional character, and details ot which are therefore not shown. This reversing engine has suitable valve gearing designated generally by the numeral 68, which may be actuated from a distance, by means oi' the apparatus designated generally by the numeral 69. inasmuch as reversing mechanism of this type is well known detailso'f construction thereof are not shown.

rllie mechanism thus `tar described constitutes what is in eliect a modified form of the Stevenson link. By suitable operation ot' the reversing engine 67 the bell crank lever 63 may be swung about its pivot to swing the rod 51 about its pivot and thus operatively connect that rod to either the upper or the vlower end ot the link 54. As shown in Fig. 1 the rod 51 is connected to the upper end of the link 54, which is the forward position, and upon oscillation of the link about its pivot point 55, under the action of the eccentric rods and 6l steam will be so admitted to the engines as to cause "forward motion ot the boat. If it is desired to reverse the motion ot the boat, as to drive it astern, the reversing engine 67 is caused to function so as to move the rod 5l to connect it to the lower end of the link 54, in,ivh'ich case the valves of the en giiies will be so actuated as to cause the desired reverse motion.

The eccentric rod 60 is connected to an eccentric str-ap 70, which in turn cooperates with the eccentric 71, which is suit-ably keyed to the shaft 72, the opposite ends of which are mounted in suitable bearings car- Y ried by the standards' 73, which are in turn supported upon the bed plate, or deck of the boat, in any suitable fashion. The eccentric rod 61 is connected to the eccentric strap 75, which cooperates with the eccentric 76, which isals'o mounted upon the shaft 7 2. As shown these eccentrics are so positioned upon the shaft as to give the desired oscillation of the link 54 during operation. This setting is entirely dependent upon the particular valve and operation that is desired, and' anyone skilled in thesteam engine art should be qualified to determineV the desired setting of the ecceiit-rics, and the other parts 'of this valve actuating mechanism.

@ne end of the shaft 72 has attached thereto a crank 80, which is provided with a slot 8l therein, in which is mounted a sliding block, in the nature of a. cross head, 82,5this construction being somewhat similar to the I wellknown Scotch yoke. This sliding blockA is pivot-ally connectedto the link 85, intermediate the ends 'of' that link, the lower end of the link being pivotally connected, in any suitable manner, to the respective connecting rod, while the upper end is pivot-ally connected to a'second link 86, the other end of which is mounted upon a shaft 87, supported.

in suitable bearings carried by the hangers 88.

As shown in Fig. lthe point of pivotal connection of the link 85, to the connecting rod will, during operation, move substantially through the path designated by the dotted line 90. As it does move through this path it will cause rotation of the shaft 7 2, the point of connection of the sliding blockV 82 with the link 85 moving substantially through the path designated by the dotted line 91. YThe shaft 72 thus has imparted thereto continuous rotary motion, which, acting through the eccentric mechanism, causes the eccentric rods 60 and 61 to im partoscillatory motion to the link 54, this in turn causing actuation of the Vvalve gear.

By means of the construction described above sellcontained actuation of the valve gearing of each engineis secured. For the mechanism for actuating the valvegearing for each particular engine is actuated by the engine itself, and not by a companion engineas is the usual case. And so not only can each engine have its valve gearing independently adjusted; but each engine may be driven alone and without being in any way Ydependent upon the operation of the other engine or engines.

While the form of apparatus herein described constitutes a preferred embodiment of the invention, it is to be understood that the invention is not limited to this precise form of apparatus, and that changes may be made in either without departing from the scope of the invention which is defined in the appended claims.

That is claimed is:

l. In apparatus of the character described, the combination of a steam engine cylinder, valves therefor; valve actuating mechanism comprising a rotatable shaft, an eccentric mounted upon said shaft, means connecting said eccentric to the valve actuating mechanism; a crank having a slot therein mounted upon said shaft, a block slidably mounted within said slot; a connecting rod for said engine, a link member pivotally connected at one end to said connecting rod intermediate the ends of said rod and pivotally connected at the other end to a second pivotally mounted link, said first mentioned link being pivotally connected to the said sliding block, at a point removed from the end thereof which is pivotally connected to the connect-ing rod.

2. In a power plant of the character described, and in combination, an engine operatively connected to a work shaft, sai-d engine comprising a power cylinder having a piston therein, a piston rod connected to said piston, a connecting rod connecting the piston rod to the work shaft; a valve wit-hin the cylinder, valve actuating mechanism associated with the cylinder; a rotatable shaft,

nism; a crank mounted upon the end of the rotatable shaft, a sliding block carried by the crank, a. pivotally mounted link pivotally connected adjacent one end to the sliding block and pivotally connected at the other end to the connecting rod, whereby reciprocating motion of the connecting rod imparts rotary motion to t-he said rotatable shaft; and adjustment means for operatively connecting the valve actuating mechanism to one eccentric or the other.

3. In a steam engine, comprising a cylinder, a piston and a valve therefor, and actuating mechanism for said valve; the combination of a crank shaft, a connecting rod connecting said crank shaft and piston, a rotatable eccentric shaft, a link pivoted at one end to a fixed support, a second link pivotally connected at one end to the free end of the first named link and at its other end to the connecting rod, a crank arm connected to the rotatable eccentric shaft, having a slot therein, a block slidable in said slot, and pivotal connection between said block and the said second link, an eccentric mounted upon said rotatable shaft, an eccentric strap cooperating with said eccentric and an eccentric rod connecting said eccentric strap to the valve actuating mechanism.

In testimony whereof I hereto affix my signature.

HENRIK GREGER. 

